Liquid fuel burner



Feb. 25, 1936. R. M. SHERMAN 2,032,334 LIQUIDFUEL BURNER lllllll Patented Feb. 25, 1936 UNEEI'D STATES PATENT OFFIICE LIQUID FUEL BURNER necticut Original application November 24, 1928, Serial No. 321,624. Divided and this application February 17, 1931, Serial No. 516,306

14 Claims.

This invention relates to that class of burners more particularly employed in connection with oil stoves, and one object of my invention, among others, is to provide a burner that shall be simple in construction, may be readily cleaned, and shall be particularly efficient.

This application is a division of my prior copending application, Serial No. 321,624, filed November 24, 1928.

The invention will be best understood by reference to the following description when taken in connection with the accompanying illustration of one specific embodiment thereof, while its scope will be more particularly pointed out in the appended claims.

In the drawing:-

Fig. 1 is a side elevation of my improved burner with parts broken away to show the construction;

Fig. 2 is a top view of the base of my improved burner;

Fig. 3 is a sectional elevation, partly broken away, taken on the line 3-3 in Fig. 4, showing the burner base and one of the supporting burner shells;

Fig. l is a top view of the device with the burner ring or cover plate and the duct cover in place but with the burner shells removed;

Fig. 5 is a detail view in section through a portion of the burner, taken on the line 55 in Fig. 4; and

Fig. 6 is an elevation in section, on the dotted line in Fig. 4, showing the duct and its cover.

Referring to the drawing and to the embodiment of my invention therein illustrated, there is provided a base or bottom plate II which may be supported in any suitable manner, as by means of a rod It. On its under surface the bottom plate has a boss l5 for the attachment of a fuel supply pipe i7. As herein shown one-half of the structure only is apparent, the structure shown being duplicated on the opposite side of the rod 3.

The plate l l is provided with a series of upright, spaced, annular, concentric flanges l9, 2|, 2'3 and in the upper surface of the plate presenting upstanding walls forming between them inner and outer fuel chambers, one a relatively broad, inner fuel chamber 27 comprising a relatively wide channel, and the other a surrounding, spaced, outer chamber 29 in the form of a relatively narrow, annular channel or groove, there being provided open fuel supply ducts 3| connecting the outer and inner chambers.

A central air supply opening 33 is formed in the bottom of the base with the inner flange I9 surrounding said opening, said flange forming one side of the channel 21. The outer flange 2| of the fuel channel 2? and the inner flange 23 of the fuel groove or channel 29 form in efiect a comparatively thick rib 35 separating the two chambers, the rib being cut through laterally at certain points to create the ducts 3| and out through vertically to provide a series of arcshaped slots 3? for the supply of air to the burner, as shown in Fig. 2 of the drawing.

Resting on and positioned by the top of the inner flange IQ of the base H there is provided a removable, annular cap or cover plate 39 having a central air opening cooperatively related to and registering with the central air opening 33 in the base.

The cover plate fits down over the inner flange l9, being depressed somewhat into the wider channel 2'! and extends from the inner flange partially across the channel, presenting a wall overlying and covering the inner part of that channel next adjacent the inner flange. This wall extends toward the opposite or outer flange 2i and has its peripheral edges terminating in closed spaced relation to the outer flange, so that there is left in the channel or chamber adjacent the outer flange a relatively narrow, uncovered portion providing a narrow, annular, peripheral opening or slot 4! communicating and aligning with the overhead combustion chamber, hereinafter referred to.

The fuel supply is admitted through the pipe I! to the bottom of the channel and preferably within the covered portion thereof.

To provide suitable combustion chambers and air supply chambers there are employed burner shells or combustion tubes in the form of spaced, annular, concentric, tubular wall members 43, 45, 41 and 46, forming thereby inner and outer, annular, combustion chambers 5| and 53: respectively, of substantially equal radial width, and an intermediate, annular, air chamber 55 between the outer and inner combustion chambers and also an inner air chamber 5'! within the inner combustion chamber and enclosed by the inner walls 43 thereof.

The walls 41 and 49 of the outer combustion chamber 53 are in surrounding and upstanding relation to the outer fuel channel 29, being supported by and fitting one within and the other y outside the flanged or shouldered edges of the upstanding, annular walls 23 and 25, respectively, of the base, so that the combustion chamber 53 is in open communication and substantial alignment with the narrow fuel channel 29.

ill

and 41.

Similarly, the walls 43 and 45 of the inner combustion chamber are in surrounding and upstanding relation to the relatively uncovered, annular opening or slot 4! of the wider, inner channel 21, the outer tube 45 being supported by and fitting over the outside flanged or shouldered edge of the upstanding, annular wall 2|, and the inner tube 43 being supported by and fitting within the peripheral flange 59 on the cover plate 39, leaving the inner combustion chamber 5i in communication and substantial alignment with the relatively narrow, uncovered portion of the wider fuel groove 21.

The intermediate air chamber 57, which is supplied through the central air opening 33 in the base, is closed at its top by a cover plate 6| seated on the upper edges of the inner combustion tube 43, and the intermediate air chamber 55v which registers with the air slots 31in the base is closed by an annular cover 53 seated on the upper edges of the combustion chambers 45 It will be understood that the burner shells or tubes are perforated to such extent as may be desired, a portion only of the perforations being shown in Fig. l of the drawing.

Burners of this class as heretofore constructed have had the disadvantage of relatively slow starting after the fuel has been first ignited and also the tendency to build up deposits of unconsumed carbon, clogging the fuel spaces and connecting ducts in positions where it is difficult of removal. Such deposits interfere with the free flow of the oil in thin film-like form in which it is best adapted for complete and rapid combustion, and such deposits themselves tend further to promote incomplete combustion.

In the described form of burner, the inner groove which receives the oil supply provides a relatively broad area over which the oil is adapted to flow and in which it is brought into close association with the overlying wall of the removable cover plate. After the first ignition of the fuel the burner heats up rapidly and the burner shells soon become red hot. The cover plate 39 underlies a part of the inner air chamber, between the latter and the inner channel. The inner air chamber is enclosed by the heated walls of the inner combustion tube'and the latter is supported by direct contact with the cover plate. The cover plate thus becomes an active agent in transmitting heat to the oil as it is supplied to the inner channel, in addition to the heat received from other sources, 'so that, soon after the first ignition of the oil, the latter tends to become wholly vaporized as soon as it reaches the wider inner channel and the fuel is supplied to the slot 4|, the ducts 3| and the outer narrow fuel groove in vaporized form. This not only reduces the time required for starting the burner, but -alsotends largely to prevent the building up of unconsumed carbon, particularly in the outer fuel groove and the connecting ducts which, during the normal operation of the burner, receive the fuel only in vaporized form, the widerinner channel acting as a vaporizing chamber supplying both combustion chambers.

When it becomes necessary, however, to clean the inner channel for the removal of such carbon deposits the entire width of the channel, including the inner or normally covered portion thereof, may be opened and revealed for cleaning purposes by the simple removal of the inner burner shell and cover plate.

The disclosed form of burner also provides a construction whereby open access to the ducts themselves may be readily had and whereby they may be easily cleaned of any obstruction when such cleaning is required.

In the construction shown, these ducts are open channels cut through the ribs 35, there being provided for each duct a separate duct cover 65 having lips 61 which rest upon shoulders 69 located at opposite sides of the duct and formed by interrupting or terminating the flanges 2| and 23 short of the duct. This is shown in Figs. 2, 3 and 6 of the drawing. Each cover is formed to removably fit between the concentric flanges overlying and resting upon the side walls of the duct, the lips 61 extending between the separated or interrupted portions of the flanges, as shown in Fig. 3. By this construction, on removal of the combustion tubes 45 and 41, the duct-cover may be readily removed and the duct cleaned. When in place, however, the duct-cover closes the duct and prevents access of air from the intermediate air chamber to the fuel spaces.

While I have herein shown and described for the purposes of illustration one specific embodiment of the invention as applied to one specific type or form of burner, it is to be understood that extensive deviations may be made in the illustrative embodiment, all without departing from the spirit of the invention.

I claim:

1. A burner of the class described having pairs of'spaced concentric annular combustion tubes forming spaced inner and outer combustion chambers with an intermediate air chamber and an inner air chamber enclosed by the inner combustion tube, a base having spaced annular upstanding walls presenting between them concentric, spaced, inner and outer fuel chambers underlying and communicating each with one of said combustion chambers, the inner one of said fuel chambers being of greater width than the outer one and extending laterally beyond the limits of the inner combustion chamber said base having openings for admitting air to the said air chambers, a removable wall overlying and forming with the laterally extending part of said wider fuel chamber a covered vaporizing space with its removable wall exposed to heat from the walls of the overlying air chamber, said removable wall having its peripheral edge adjacent the inner combustion chamber in spaced relation to the wall of said wider fuel chamber to provide an annular opening establishing the communication between said inner fuel and combustion chambers, and means for supplying fuel to said outer fuel chamber through said inner fuel chamber and vaporizing space.

2. A burner of the class described having pairs of spaced concentric annular combustion tubes forming spaced inner and outer combustion chambers with an intermediate air chamber and an inner air chamber enclosed by the inner combustion tube, a base having spaced annular upstanding walls presenting between them concentric spaced inner and outer fuel chambers underlying and communicating each with one of said combustion chambers, the inner one of said fuel chambers being of greater width than the outer chamber, said base having openings one into each of said air chambers and having fuel supply ducts connecting said two chambers, a removable cover plate resting on the inner wall of said wider fuel chamber and overlying a part thereof and exposed to heat from the walls of h adja ent a amber to provide a vaporizin pa ben a h the am but having its outer p ripheral edges spaced from the outer wall of said fuel chamber to provide an annular uncovered portion in said chamber registering with the inher combustion chamber for establishing the communication thereto, said cover plate serving as a support for a combustion tube, and means for supplying fuel from below to the bottom of said vaporizing space and through said inner fuel chamber to said outer fuel chamber.

3. A combustion tube burner having a base provided with laterally spaced fuel chambers, one of which is relatively narrow and surrounds the other, said other chamber being enlarged to provide a vaporizing space, a fuel supply conduit connecting said two chambers, inner and outer sets of perforated walls forming between them a plurality of combustion chambers in communication with and in upstanding relation one above each of said fuel chambers and forming also an intermediate air chamber between the combustion chambers and an inner air chamber within the inner combustion chamber, means for supplying air to said air chambers, a wall overlying and covering a part of the inner fuel chamber but having its peripheral edges terminating short of the outer wall thereof to close the top of the vaporizing space and provide a relatively narrow uncovered opening at the outer side of the inner chamber establishing the communication to the overhead combustion chamber, said wall underlying said inner air chamber between the latter and the inner fuel chamber, and means for supplying liquid fuel to said vaporizing space.

4. A combustion tube burner having a base provided with laterally spaced fuel chambers, one of which is relatively narrow and surrounds the other, said other chamber being enlarged to provide a vaporizing space, fuel supply ducts connecting said two chambers, inner and outer sets of perforated walls forming between them a plurality of combustion chambers in communication with and upstanding relation one above each of said fuel chambers and forming also an inter mediate air chamber between the combustion chambers and an inner air chamber within the inner combustion chamber, means for supplying air to said air chambers, a removable cover plate resting on said base, said plate covering a part of said enlarged inner fuel chamber and having one of its peripheral edges adjacent said inner combustion chamber in spaced relation to the adjacent side of said inner fuel chamber to close the top of the vaporizing space and provide a relatively narrow uncovered opening registering with the overhead combustion chamber, said cover plate supporting a wall of said inner combustion chamber and underlying and exposed to the heat of the air chamber adjacent the thus supported wall, and means for directly conducting liquid fuel only to said enlarged inner fuel chamber.

5. A burner including a base having a plurality of concentric, laterally spaced, annular, open fuel channels, one of which is large and the other relatively small in radial width, said other chan-- nel surrounding the radially larger channel, a plurality of open ducts connecting the channels, combustion tubes surrounding the tops of the channels and extending upwardly thereabove, a cap which rests removably on said base and overlies the top of the larger channel and constitutes a support for one of said tubes, said cap having an air passage therethrough which communicates with the interior of the tube thereon, covering means for said several ducts separate from said cap, and means to introduce liquid fuel into the bottom of the larger channel only.

6. A liquid fuel burner having spaced concentric combustion tubes forming spaced inner and outer combustion chambers with an intermediate air chamber and an inner air chamber enclosed within the inner combustion tube, a base surmounted by said combustion tubes and having openings for admitting air tothe said air chambers, said base having laterally spaced interconnecting open endless vapor distributing channels terminating in inner and outer delivery portions, one surrounding the other, said delivery portions being beneath the combustion chambers and delivering one to the outer combustion chamber and the other to the inner combustion chamber, said base presenting an open topped vaporizing portion positioned laterally of and communicating with the inner of said delivery portions and underlying one of said air chambers, a removable cover plate resting on the base covering said laterally positioned vaporizing portion and underlying and exposed directly to the heat from the walls of said 1 air chamber overlying said vaporizing portion, said cover plate having a continuous edge bordering the inner of said delivery portions and said plate also serving as a support for a combustion tube, and means for supplying liquid fuel to said vaporizing portion.

'7. A liquid fuel burner having spaced concentric combustion tubes forming spaced inner and outer combustion chambers and defining an intermediate air chamber and an inner air chamber enclosed within the inner combustion tube, a base having laterally spaced interconnected open endless vapor distributing channels terminating in upwardly directed delivery portions one surrounding the other, said delivery portions be, ing beneath the combustion chambers and reg.- istering one with the outer combustion chamber and the other with the inner combustion chamher, said base having openings for admitting air to the said air chambers topped vaporizing portion communicating with said upwardly directed delivery portions and positioned to underlie one of the said air chambers, a removable cover plate resting on the base covering the top of said vaporizing portion and exposed directly to the heat from the combustion tube walls of the overlying air chamber, said cover plate having a continuous edge borderin the adjacent upwardly directed delivery portion and said plate also serving as a support bustion tube thereabove, and means for suppiying liquid fuel to said vaporizing portion.

8. A liquid fuel burner having spaced concentric combustion tubes forming inner and outer combustion chambers with an intermediate air chamber and an inner air chamber enclosed within the inner combustion tube, a base surmounted by said combustion tubes and having openings for admitting air to said air chambers, a removable cover plate resting on the base as a support for a combustion tube and underlying and exposed directly to the heat from the combustion tube walls of one of said air chambers, said base having formed therein intercommunieating channels for the vaporization and distribution of fuel and which present laterally spaced endless inner and outer vapor delivery portions and a vaporizing portion, said vapor delivery portions underlying the respective combustion chambers and delivering upwardly thereto andsaid and having an open for a 'comand serving vaporizing portion underlying said cover plate and separated from the overlying air chamber thereby, said cover plate having a continuous edge bordering one of said endless vapor delivery portions, and means for supplying liquid fuel to said base for vaporization under said cover plate and delivery to said combustion chambers through said inner and outer vapor delivery portions.

9. A liquid fuel burner having pairs of spaced, concentric, combustion tubes forming between them annular, inner and outer combustion chambers and forming also an intermediate air chamber within the combustion chambers and an inner air chamber within the inner combustion tube, a base surmounted by said combustion tubes, a removable cover plate resting on said base and positioned beneath said inner air chamber and exposed to the heat from the walls thereof, said base having formed therein interconnecting channels for the vaporization and distribution of fuel and which present laterally spaced, annular, outer and inner vapor delivery portions and a vaporizing portion, said vapor delivery portions underlying and delivering upwardly to said respective combustion chambers and said vaporizing portion underlying said cover plate and separated from said inner air chamber thereby, said base having a plurality of spaced, open ducts-connecting said vapor delivery portions and having also air supply openings between the walls of said ducts communicating with said intermediate air chamber and an air supply opening communicating with said inner air chamber, covering means for said several open ducts separate from said cover plate, and means to introduce liquid fuel to said base and beneath said cover plate.

10. A burner having pairs of spaced concentric combustion tubes forming between them inner and outer combustion chambers, a burner base having open, laterally spaced, inner and outer annular vaporizing and distributing channels providing upwardly directed vapor delivery openings and vapor distributing portions underlying said openings and one surrounding the other, said vapor delivery openings being aligned with said combustion chambers, said base having open spaced ducts connecting said vapor distributing portions and having also an open inner fuel vaporizing portion concentrically related to said vapor distributing portions and communicating with the inner of said vapor distributing portions, a removable cover plate to close said inner open vaporizing portion, separate removable covering means for said open ducts, and means for supplying liquid fuel to said vaporizing portion beneath said cover plate.

11. A liquid fuel burner having spaced, concentric combustion tubes forming inner and outer combustion chambers with an intermediate air chamber and an inner air chamber enclosed within the inner tube, a base surmounted by said combustion tubes and comprising an inner, radially broad, annular base portion and an outer, relatively narrow, annular base portion spaced from andsurrounding said inner base portion and having connections thereto at intervals, said base having openings between said connections for supplying air to said intermediate air chamber and an opening within said inner base portion for supplying air to said inner air chamber, said inner and outer base portions having vaporizing and distributing passages including annular, inner and outer, vapor distributing portions in said respective base portions beneath and opening into said inner and outer combustion chambers, respectively, and said connections having ducts connecting said vapor distributing portions, said vaporizing and distributing passages including also an open vaporizing portion in said broad inner base portion and communicating with said vapor distributing portions, a removable cover plate resting on said base beneath said inner air chamber and exposed to the heat from the walls thereof, said plate covering said open vaporizing portion to form therewith a vaporizing chamber, all portions of said cover plate terminating short of the inner, annular, vapor distributing portion, and means to introduce liquid fuel to said burner.

12. A liquid fuel burner comprising pairs of spaced, concentric, annular, vertically arranged, combustion tubes forming spaced inner and outer combustion chambers with an intermediate air chamber therebetween and an inner air chamber' enclosed by the inner combustion tube, a base :5,

having an outer pair of relatively closely-spaced, annular, upstanding walls presenting between them a relatively narrow outer fuel chamber with a closed bottom and an open top lying below and communicating with the outer combustion chamber, and an inner pair of relatively widely-spaced, annular, upstanding walls presenting between them a relatively broad, inner fuel chamber with a closed bottom and an open top having only a minor portion of its breadth adjacent its outer annular wall underlying and communicating with said inner combustion chamber and having its major portion extending under said inner air chamber, said base having openings for admitting air vertically therethrough into each of said spaced from the outer wall of said fuel chamber ,4

and supporting thereat the said inner combustion tube, the remainder of its top' surface being at least as low in vertical elevation as the portion thereof resting upon the inner upstanding wall of the base and thus out of the path of cool air admited vertically into said inner air chamber, and means for supplying liquid fuel from below directly to the bottom of the covered portion of said inner fuel chamber, whence it may pass'to the outer portion of the inner fuel chamber and 1 through said ducts to the outer fuel chamber and be retained therein during the starting of the burner, said cover plate being furthermore in quick heating relation to the walls of said inner combustion tube and being closely spaced above 1 the bottom of the underlying major portion of said relatively broad fuel chamber to be in quick vaporizing proximity to liquid fuel admitted to the bottom of said covered portion, said covered portion constituting during the operation of said v burner a common quick vaporizing and vapor supply space for both said combustion chambers, closed except for its communication with said combustion chambers and from which air is excluded during the operation of the burner.

13. A liquid fuel burner comprising pairs of spaced, concentric, annular, vertically arranged,

combustion tubes forming spaced inner and outer combustion chambers with an intermediate air chamber therebetween and an inner air chamber enclosed by the inner combustion tube, a base having an outer pair of relatively closely-spaced, annular, upstanding walls presenting between them a relatively narrow outer fuel chamber with a closed bottom and an open top lying below and communicating with the outer combustion chamber, and an inner pair of relatively widely-spaced, annular, upstanding Walls presenting between them a relatively broad, inner fuel chamber with a closed bottom and an open top having the outer portion of its breadth adjacent its outer annular wall underlying and communicating with said inner combustion chamber and having the inner portion of its breadth extending under said inner air chamber, said base having openings for admitting air vertically therethrough into each of said air chambers and having also lateral fuel supply ducts connecting the two fuel chambers, the bottoms of said ducts being below the tops of the upstanding walls forming said chambers, an annular, removable cover plate closing the top of said inner portion of said inner fuel chamber resting adjacent its inner annular portion upon the inner upstanding wall thereof and supporting adjacent its outer annular edge the said inner combustion tube, said cover plate having its outer peripheral edge spaced from the outer wall of said fuel chamber, and means for supplying liquid fuel from below directly to the bottom of the covered portion of said inner fuel chamber, whence it may pass to the outer portion of the inner fuel chamber and through said" ducts to the outer fuel chamber and be retained therein during the starting of the burner, said cover plate being in quick heating relation to the walls of said inner combustion tube and being closely spaced above the bottom of the inner portion of said' relatively broad fuel chamber to be in quick vaporizing proximity to liquid fuel admitted to the bottom of said covered portion, said covered portion constituting, during the operation of said burner, a common quick vaporizing and vapor supply space for both said combustion chambers.

14. A liquid fuel burner having pairs of spaced, concentric, combustion tubes forming between them annular, inner and outer combustion chambers and forming also an intermediate air chamber with the combustion chambers and an inner air chamber within the inner combustion tube, a base surmounted by said combustion tubes, a removable cover plate resting on said base and positioned beneath said inner air chamber and exposed to the heat from the walls thereof, said base having formed therein interconnecting channels for the vaporization and distribution of fuel and which present laterally spaced, annular, outer and innervapor delivery portions and a vaporizing portion, said vapor delivery portions underlying and delivering upwardly to said respective combustion chambers and said vaporizing portion underlying said cover plate and separated from said inner air chamber thereby, said base having an open duct connecting said delivery portions and having also air supply openings on opposite sides of the walls of said duct communicating with said intermediate air cham- 

